60 students of Section A of Class XI, obtained 40 mean marks in Statistics, 40 students of Section B obtained 35 mean marks in Statistics. Find out mean marks in Statistics for Class XI as a whole.

5 students obtained following marks in Statistics: 20,35,25,30,15 Find out range and coefficient of range.

For 50 students of a class, the regression equation of marks in Statistics(X) on the marks in accountancy(Y) is 3y-5x+180 =0 .The mean marks in accountancy is 44 and the variance of marks in Statistics is (9/16)th of variance of marks in Accountancy .Find the mean marks in Statistics and the correlation coefficient between the marks of the two subjects.

The mean mark in statistics of 100 students in a class was 72. The mean mark of boys was 75 while their number was 75. The mean mark of girls in the class was

The mean mark in Statistics of 100 students in a class was 72 .The mean mark of boys was 75, while their number was 70. The mean mark of girls in the class was

Find the mean of the marks obtained by 30 students of class IX of a school. The marks are

For 50 students of a class, regression equation of marks in statistics (x) on marks in Accountancy (y) in 3y-5x+180=0 . The mean in Accoutancy is 44 and the variance of marks in statics is 9/16 of the varience of marks in Accountancy. Find the mean marks in Statistics and coefficient of correlation between marks in two subjects.

Following are the marks obtained by 20 students in statistics. Find out coefficient of variation of the marks.

Find the mean of the marks obtained by 30 students of class IX of a schoo.

In a class of 15 students, the total marks obtained by all the students in a test is 600. Find the average mark of the class.